Hydraulic lines may include all lines which are suitable for the passage of liquids or mixtures of liquids and gases. Lines of this type can be used, for example, as part of a fuel supply system, such as in a motor vehicle, and in the supply of a heating system, a power plant or the like. The fuel supply system of a motor vehicle, which is driven, for example, by a spark ignition or diesel internal combustion engine, typically has a fuel tank with an active or passive delivery module in order to supply the internal combustion engine with fuel via fuel lines. Fuel lines of this type comprise a multiplicity of line elements which can be designed, for example, in the form of tubes, flexible hoses or the like.
Since a fuel supply system includes a multiplicity of components, it is expedient to be able to couple the individual components in a simple manner and optionally also to be able to release them from one another again. For a releasable fastening of hoses, connectors are known, as described, for example, in U.S. Pat. No. 4,729,583. The connector presented therein includes two parts, wherein, in particular, good sealing to the hose and a stable design are intended to be made possible.
In a fuel supply system, the risk of an electrostatic charge may also be taken into consideration. Since fuel flows through the various components of the fuel supply system, such as through a primary fuel pump, optionally provided auxiliary pumps, through a fuel filter or through various valves and pipes, an electrostatic charge generated in the various conductive components of the fuel supply system may occur. In order to ensure electrical dissipation of such a charge, in fuel supply systems the components in the fuel flow or all of the components are constructed of conductive material and are coupled to the vehicle ground. This generally takes place by electric lines or else by direct fitting to the vehicle ground.
Dissipation of a possible electrostatic charge is readily possible in components of the fuel supply system that are produced from electrically conductive material, such as from metal and conductive polymer. However, materials of this type have a number of disadvantages. For example, conductive plastic is customarily more expensive and more brittle than nonconductive polymers which are typically used.
In order to deliver fuel from the delivery module/module pot to the associated flange, use is customarily made of a corrugated hose. The latter is customarily coupled nonreleasably to the flange and the delivery module via connectors with shaped profiles. It has turned out that a hose of this type has to be grounded for reliable operation of a motor vehicle. Said hoses are therefore entirely electrically conductive or are electrically conductive at least on the inside thereof, where said hoses are also in contact with the fuel.
Fuel supply systems are furthermore known, for example from DE 10 2005 061 606 A1, which contain a fuel delivery module which is arranged within a fuel tank. A delivery module of this type has a store for collecting the fuel from the tank and for conducting said fuel on to the internal combustion engine, and it may also contain a fuel pump. A fuel filter can be arranged within a delivery module of this type or at another location within the tank. In order to arrange the fuel delivery module and also the fuel filter within the tank, it is also known to use a tank flange which permits various inlets into the tank, such as via hydraulic and electric lines.
It is precisely in a tank flange of this type that the brittleness of electrically conductive polymers results in a reduction in the capability of being flexible in the event of loading or of withstanding forces determined in another manner, as may occur, for example, in the event of the motor vehicle having an accident. Furthermore, in the case of a conductive tank flange, electric insulation with respect to the electric power supply plug-in connectors arranged on the upper side and the picking up of signals from the level sensor are required.
The inventor herein has recognized the issues with the above approaches and provides a system to at least partly address them. In one embodiment, a coupling system comprises a hose-like element including an electrically conductive inside, a hydraulic line element, and a connecting element coupling the hose-like element to the hydraulic line element. The hose-like element includes an inverted double-walled end that houses part of the connecting element, and the inverted double-walled end is configured such that a portion of the electrically conductive inside is on an outside thereof. The coupling system also includes an annular fastening element in electrical contact with the outside of the inverted double-walled end of the hose-like element.
In this way, an end piece of the hose-like element—also called a hose—is guided over a connection of the hydraulic line and, in addition, is turned up in such a manner that a double layer of the hose wall is produced in sections and part of the inside of the hose points outward. Said inside is in electrical contact with a fastening element which is at least partially annular. The fastening element, which may be, for example, a clamping ring, a clamping clip or the like, presses the double layer of the hose wall onto the connection of the hydraulic line and thereby additionally brings about secure and tight coupling between the hose and the hydraulic line. In addition, by a suitable mechanism, such as a metal wire, the inside of the hose can be coupled to a predetermined potential, such as the ground potential of a motor vehicle, via the fastening element.
Because the inside of the hose which faces outward is itself conductive and coupled to a conducting device, electrostatic charge may be directed from the conductive interior of the hose to the conductive device and one or more grounded elements. This may allow the flange to be made of non-conductive materials, increasing the flange flexibility and improving component durability. By doing so, a coupling element for coupling a hose-like element to a hydraulic line may be provided, in particular a tube, and may prevent or dissipate electrostatic charges in a simple manner, and additionally also provide the option of producing a particularly tight coupling.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.